The objective of this research is to better understand the perception of complex auditory stimuli. The means by which this is to be achieved is by consideration of the representation of acoustical stimuli, and in particular the relationship between the representation of temporal and intensity aspects of the acoustical stimuli. The experiments are designed to, one the one h and, determine whether models which treat temporal and intensity information as being independently coded manner in which temporal and intensity information as being independently coded are able to account for psychophysical data, and on the other hand, examine the manner in which temporal and intensity information is combined both on either temporal or intensity information. A second experimental manipulation requires discriminations between complex sounds that vary systematically in terms of three features: intensity, envelope modulation and phase modulation. The ability to discriminate between such stimuli allows an estimation of the relative contribution of these features for the formation of complex auditory percepts, and allows an initial evaluation of the means by which these features are represented in the auditory system. The basic information concerning temporal and intensity processing in the auditory system that will result from this plan of study may provide a basis for the diagnosis and treatment of auditory impairment. Particularly important is the development of a means by which temporal and intensity processing may be independently tested.